Effects of torasemide on cardiac sympathetic nerve activity and left ventricular remodelling in patients with congestive heart failure.

Abstract

To determine the effect of torasemide, a loop diuretic with antialdosteronergic properties, compared with furosemide on cardiac sympathetic nerve activity in patients with congestive heart failure (CHF). 40 patients with non-ischaemic CHF (left ventricular ejection fraction (LVEF) < 45%) were randomly assigned to torasemide (4-8 mg/day; n = 20) or furosemide (20-40 mg/day; n = 20). All patients were also treated with angiotensin-converting enzyme inhibitor. The delayed heart to mediastinum count (H/M) ratio, delayed total defect score (TDS) and washout rate were determined from iodine-123 meta-iodobenzylguanidine measured before and 6 months after treatment. Left ventricular end diastolic volume (LVEDV), left ventricular end systolic volume (LVESV) and LVEF were also determined by echocardiography. After treatment, in patients receiving torasemide, TDS decreased from 44 (8) to 36 (8) (p < 0.001), H/M ratio increased from 1.61 (0.19) to 1.77 (0.24) (p < 0.001), and washout rate decreased from 52 (12)% to 41 (14)% (p = 0.001). In addition, LVEDV decreased from 173 (22) ml to 147 (30) ml (p < 0.001) and LVESV decreased from 117 (19) ml to 95(24) ml (p < 0.001). Although LVEF tended to increase, the change was not significant (from 31 (7)% to 34 (7)%, NS). Conversely, these parameters did not change significantly in patients receiving furosemide. Moreover, percentage change of TDS was significantly correlated with percentage change of LVEDV (r = 0.473, p < 0.05) and of LVESV (r = 0.579, p < 0.01) after torasemide treatment. These findings indicate that torasemide treatment can ameliorate cardiac sympathetic nerve activity and left ventricular remodelling in patients with CHF.